1) Field of the Invention
This invention relates to caps for threaded outlets. More particularly, it relates to tare caps for valve outlets. The caps have been modified so as to make it possible to put the cap on the threaded outlet, but impossible to remove without breaking a tear strip. The breaking of the tear strip makes it possible for the owner to determine that the threaded outlet has been used by an unauthorized individual.
2) Description of the Related Art
A variety of caps have been developed or proposed wherein an initial opening of a lid or a dispensing spout structure provides visual evidence of such an occurrence—even after the lid or spout has been subsequently closed.
U.S. Pat. No. 4,595,123, issued to Libit Jun. 17, 1986, discloses a tamper-evident closure cap having a pivotable stopper closing a cap top orifice. The stopper has an integral flange overlying portions of the top and extending behind the pivotable member to preclude pivoting of the pivotable member. The flange is removable from the pivotable member and indicia formed in the container top underlying the flange is made visible by removal of the flange.
U.S. Pat. No. 4,711,363, issued to Marino Dec. 8, 1987, discloses a tamper-evident closure having a multiple cap configuration intricately joined to a closure by a live hinge. A secondary cap is formed within the first cap with frangible tamper-evident strips and a secondary live hinge. A tubular plug depends from the underside of the secondary cap and is capable of going into a dispenser opening within the closure. Assembly pins secure the cap to the closure and an annular rib on the tubular plug forms a seal around the dispensing opening when the tubular plug is in a closed position and holds the secondary cap and plug in the closed position once the frangible tear strips are broken.
U.S. Pat. No. 5,579,943, issued to Johnson Dec. 3, 1996, discloses a dispensing closure lid having a tear-away tab for use with a container. The tab is configured with an outwardly extending grasping member. The tab is defined by a distinct sequence of slits and perforations wherein the slits have a greater length than the perforations. The specific sequence of slits and perforations facilitates removal of the tab from the container mouth and provides for a clean separation of the tab from the land surface of the container and the remaining lid without tearing into the lid.
U.S. Pat. No. 5,769,277, issued to Elliot Jun. 23, 1998, discloses a container and a closure including a base. The base includes a body for mounting to the container, and the body defines a dispensing orifice. A tamper-evident seal initially closes the dispensing orifice. The seal has a removable central portion occluding the orifice and at least a first frangible web defining a closed tear path lying in a plane connecting the sealed central portion to a surrounding part of the closure. The sealed central portion includes a hollow projection having a base located in the plane with one part of the base closer to the first frangible web than is any other part of the base. An outwardly directed force of sufficient magnitude applied to the projection will produce a tear which extends through the first frangible web at a point on the first frangible web closest to the one part of the projection base. The tear thereafter propagates from that point around the seal central portion so as to separate the sealed central portion from the closure and thereby open the seal.
U.S. Pat. No. 6,073,809, issued to Long, Jr. Jun. 13, 2000, discloses a substantially leak proof tamper-evident container closure that combines a reusable, push-pull spout with a snap-on tamper evident closure which is substantially tamper proof. The closure has first and second locking members characterized by the first locking member having an inward flange with an upturned locking edge forming an annular groove in the flange. The pour spout with an opening therein which is partially closed by a second top having a secondary opening therein and a plug space above it with upwardly angled legs is formed integrally with the closure. Integrated into the periphery of the secondary opening is at least one annular flange. The annular flanges engage and create a sealing contact with the annular surface of the plug to provide a seal which is leak proof after many uses. The lower edge of the pour spout contains a tamper-evident band to indicate if the pour spout has been tampered with.
U.S. Pat. No. 6,655,553, issued to Staniszewski et al Dec. 2, 2003, discloses a tamper-evident assembly including a cap and a surrounding tamper-evident cylindrical side. The tamper-evident cylindrical side is initially engageable with a retaining element of the container located below the cap to prevent axial upward displacement of the cylindrical side with respect to the container. The cylindrical side includes a retention member overlying the cap to prevent manipulation of the cap to an open condition. The cylindrical side also includes a frangible tear strip arranged to be torn to facilitate removal of the cylindrical side to permit manipulation of the cap to an open condition.
U.S. Pat. No. 6,685,061, issued to Wolf et al Feb. 3, 2004, discloses a tamper-evident closure assembly for a valve outlet of a pressurized container. The closure includes a cap which rotatably engages the outlet. A tamper-evident ring is carried by the cap and has at least one projection. Rotation of the cap in a cap removal direction is opposed by engagement of the projections with a surface of the associated outlet until a portion of the ring or cap breaks, allowing the cap to be removed from the associated outlet.
While the prior tamper-evident closures are satisfactory for their purposes, they are more complex than necessary. They have more parts than is required. The parts they do have are complicated in nature and require intricate machining for producing the molds for manufacturing the closures.